女性，24岁。3个月来感四肢乏力，晨轻暮重。患者新斯的明试验阳性，乙酰胆碱受体抗体滴

阅读理解。

     We have a PE (体育) class this morning. It is very interesting. First, we do some warm-up exercises

(热身运动). It's relaxing. Then, our PE teacher teaches us to play tennis. We watch him very carefully.

Later, we play in pairs. Some boys can play very well. They come to teach us. Our PE teacher is very glad

to see this. He says our school has many clubs. "Do you like sports?" "Yes, we do." We answer. "You can

join one club and do more sports after school." he says.

1. What do they learn (学习) in the PE class?

A. Some warm-up exercises

B. To play tennis.

C. To run.

D. To play basketball

2. The PE class sounds ______.

A. boring

B. interesting

C. difficult

D. relaxed

3. Does the writer (作者) like the PE class?

A. Yes, she does.

B. No, she doesn't.

C. She doesn't like tennis.

D. Yes, she is.

4. The PE teacher ______.

A. teaches them to play soccer

B. is not fun

C. asks them to join school sports club

D. is strict

5. Boys like sports and play well and girls ______.

A. don't like it

B. play it well, too

C. like it but don't play well

D. dislike

奶油中有一种只含C、H、O的化合物A。A可用作香料，其相对分子质量为88，分子中C、H、O原子个数比为2:4:1。

(1)A的分子式为___________。

(2)写出与A分子式相同的所有酯的结构简式：___________。

已知：①ROH+HBr（氢溴酸）RBr+H₂O

②

(3)写出A→E、E→F的反应类型：A→E___________、E→F__________

(4)写出A、C、F的结构简式：A_____________、C__________、F___________。

(5)写出B→D反应的化学方程式：__________________________。

(6)在空气中长时间搅拌奶油，A可转化为相对分子质量为86的化合物G，G的一氯代物只有一种，写出G的结构简式：_____________。A→G的反应类型为__________。

简述藻类对水体的净化作用机制。

根据《深圳经济特区道路交通安全违法行为处罚条例》规定，机动车驾驶人违反道路交通安全法律、法规被处暂扣三个月以上机动车驾驶证处罚的，处依法处罚外，应当到公安机关交通管理部门指定的地点接受六小时的道路交通安全教育。

某二叉树结点的前序序列为F，C，A，D，B，E，G，H，P，对称序序列为A，C，B，D，F，E， H，G，P，则该二又树对应的后序序列为

A．A,B,D,C,H,P,F,E,G

B．A,B,D,C,H,P,G,E,F

C．A,B,H,D,C,P,G,E,F

D．A,D,C,H,B,P,G,E,F